There are a number of different known methods of edge deletion and separation that are based on different techniques and invariably carried out one after the other at different machining stations within a production line, i.e., by means of different machines or systems.
This entails capital expenditure for two different machining stations, floor space for the two machining stations and, in addition to the process times required for edge deletion and separation, auxiliary process times for handling and alignment procedures that are required in both machining stations.
A machining station different from this type of machining station is disclosed in DE 91 06 843 U1.
The prior art used as the starting point in DE 91 06 843 U1 comprises a machining station in which raw glass panels are separated into a plurality of individual glass panes and a second machining station in which the individual glass panes are subjected to edge deletion.
Possible methods of edge deletion based on the prior art described in DE 91 06 843 U1 include a thermal method using an oxygen-acetylene flame and mechanical stripping methods using grinding and polishing disks or sandblasting.
The disadvantage is that, to carry out the two machining steps, i.e., separation and edge deletion, two separate machining stations are required.
DE 91 06 843 U1 proposes to depart from the previous principle of deleting the edges of the already cut finished individual glass panes and henceforth, prior to separating [the substrate] into the individual glass panes, to remove the coating from the raw glass panels in the regions in which the score lines and separation lines for the subsequent separation are located (edge strips).
Compared to the edge deletion of individual glass panes, this generally reduces the handling time. In addition, it is said to be possible to score and cut the individual glass panes and remove the coating in a single machining station of the production line.
In this machining station, the raw glass panel is stationarily attached to a horizontal or vertical bearing surface, and an abrasive tool is used to travel along the edge strips of the individual glass panes. After the coating has been removed from the machined regions, the raw glass panel can remain standing or lying, without changing its position, and the glass cutting wheel can subsequently travel along the same path that was followed during the abrasion step. Subsequently, the individual glass panes are separated. In this manner, it is possible to use the same control program and the same motion unit to carry out both machining procedures simply by changing the tool.
A system as disclosed in DE 91 06 843 U1 for removing the coating and for cutting comprises a machining bridge on which an abrasive tool and/or a cutting tool is/are disposed for exchangeable use.
First, the abrasive tool, which is preferably controlled by a computer, is moved along a predefined path that is determined by the location of the edge regions. Once the abrasion step has been concluded, the cutting tool travels the same path along the center line of the strips from which the coating has been removed. It is claimed that grinding and cutting can be carried out simultaneously, but no details are given.
Compared to machining in separate machining stations, a solution as disclosed in DE 91 06 843 U1 has the advantage that it requires less floor space and less capital expenditure, and it increases [sic] the cycle time by shortening the auxiliary process times for handling and alignment procedures.
Reducing the cycle time by shortening the total process time by performing the edge deletion operation at the same time or overlapping in time with the separation operation is possible only if the machining paths are always oriented in the same direction and if the tool always follows the same direction of movement. Only then are the abrasive tool and the scoring tool, which can be disposed movably in tandem one after the other on a bridge, in the required position relative to each other.
DE 20 2008 005 970 U1 discloses a method and a system for deleting the edges of thin-layer solar modules by means of a laser beam.